How to count the total amount of similar rows in a MySQL query

Question

I need help with a MySQL query to count the number of times a combination of the same age_from and age_to occur.

Sample data:

 age_from   age_to
+---------+-------+
  18      |   100
  30      |   75
  18      |   50
  18      |   100
  30      |   75
  18      |   50
  30      |   75
+---------+------+

Desired result:

18 to 100 = 2
30 to 75 = 3
18 to 50 = 2

I have already tried this:

SELECT
`p_age_from` AS `age_from`,
`p_age_to` AS `age_to`,
COUNT(`p_age_from`) AS `user_count`
FROM `user`
GROUP BY `p_age_from`, `p_age_to`
ORDER BY `p_age_from`

Answer 1

You can use CONCAT to join the age_from and age_to values. Then use this to group and count the data:

SELECT
CONCAT(`age_from`,' to ',`age_to`) as 'grouping',
COUNT('grouping') AS `user_count`
FROM `user`
GROUP BY grouping

Answer 2

You can get your result using following query

SELECT CONCAT(age_from,' to ',age_to,' = ',count(age_to)) as 'age_from to age_to' FROM user GROUP BY age_from, age_to ORDER BY age_from;